Table Of ContentScopus24:21-32,July2004
A
preliminary survey of the avifauna of
Eminit Forest, Loima Hills, western
Turkana
District
Marc Baker
Eminit Forest, located in the Loima Hills of northern Kenya, is an
essential part of the grazing lands of the Turkana people. The Turkana
people are sub-divided into 17 groups, with five of these groups, the
Ngisir, Ngimonia, Ngikamatak, Wayakwara and Lukumong, depending
on the Loima ecosystem for dry season grazing (Oba 2001). Through
tribal agreements the Turkana people have created an indigenous land-
use system which is enforced by the tribal chiefs and adhered to the
majority of the time. Eminit forest not only provides dry season grazing
but also a refuge during periods of tribal instability and sporadic clashes
that occur between the Turkana and Karamajong. As reported by
Barrow (1988) and Oba (2001) the conservation of biodiversity at this
site is not related to external management but indigenous knowledge
and land-use, which has evolved out of a need to protect the natural
resource for use during times of environmental stress and tribal
instability. In terms of their effect on localised rainfall patterns and
water catchment, the Loima Hills, and Eminit Forest in particular, are
extremely valuable to the local pastoralist inhabitants as well as resident
and migratory fauna.
The main aims of this survey were to establish a bird species list and
note any species of conservation concern that may occur in the forest.
An assessment of the threats to those species was made as part of a
report for the UNDP/GEF Crossborder Biodiversity Project which was
conducting a forest conservation project in the district.
Study site
The Loima Hills (also known as Murua Ngithigerr) are situated at
03°30'N, 35°00'E covering an area of approximately 160 kml Combined
with the Puch Prasir plateau they cover a total area of 3000 km^
representing one of the most extensive highland areas in Turkana
District. Eminit Forest is situated on the Loima Hills plateau, from an
m
altitude of 2050 to a forested peak on its southern edge at 2286 m. The
km km
forested plateau is 9 at its widest point (east to west axis), 15.8 at
its longest point (north to south axis) and covers an area of
approximately 83 km^ (all values measured from 1:250 000 map, series
Y503, sheet NA-36-4, 1975). The lower slopes of the Loima Hills are
accessed by bush road, a distance of 55 km east-north-east of Lodwar,
22 Marc Baker
the provincial capital of Turkana District. Approximately 9 km (10%) of
the western edge of Eminit Forest is located in Kenya bird atlas square
12D, the remainder being located in square 13C (Lewis & Pomeroy
1989).
The forested plateauis relatively flatwith an altitudinal range of only
m
200 over an area of 83 km^ but the edges of the Loima Hills consist of
steep slopes and cliffs which create an irregular drainage pattern over
bare rock. Although there are more established drainage lines, no
flowing water was observed in May 2001. The west and north-west
slopes of the Loima Hills drain into the upper Tarach catchment system,
the south and south-east areas into the Kosipur-Turkwell catchment and
the Kaulathe-Turkwell catchments system drains the north-eastern
slopes of the mountain (Barrow 1988).
The vegetation of the Loima Hills area is related to elevation more
than terrain. The lower slopes largely comprise Aristida mutabilis and
Acacia mellifera with Acacia tortilis dominating the vegetation along
seasonal water courses and drainage lines. The soils are generally rocky
and composed of euteric outcrops and calcic cambisols. The dry
montane forest is dominated by Juniperus procera, Olea europea, Olea
capensis, Tech nobilis and Podocarpus falcatus, while the sparse
undergrowth is composed of Maytenus heterophylla, Domheya goetzenii
and Pistacia aethiopica (Barrow 1988). The forest interior comprises
mainly Podocarpus falcatus with Juniperus procera, with the latter
dominating along ridges. These dominant species form a loose canopy
at an estimated 25-30 m, with Olea europea and O. capensis forming a
sub-canopy at an estimated 10-15 m. In approximately 65% of the forest
visited, there was very little undergrowth, with saplings forming much
of the vegetation structure between ground level and 5 m. There were
occasional shrubs where breaks in the canopy had allowed light to
penetrate, forming islands offorest edge habitat within the forest.
Large amounts of dead wood and leaf litter covered the forest floor
providing a micro-environment for large numbers of invertebrates.
Much of this dead wood seemed to be very old and the rate of
decompositionslow which is possibly linked to the lack of moisture.
Methods
A combination of mist-netting, timed species counts (TSCs) and ad hoc
observation were used to survey the avifauna in Eminit Forest over a
period of ten days from the 30 April to 9 May 2001. Mist netting was
carried out from 06:00 to 12:00 and 16:00 to 18:30. All birds caught were
fitted with a standard Museum of Nairobi ring and the following
biometric measurements were taken: tarsus, wing, bill, tail length and
weight. These data, along with brood patch (six point scale from O=none
to 5=full) and moult data were deposited with the National Museum of
Kenya, Nairobi.
Avifauna of Eminit Forest, Loima Hills 23
Timed species counts were carried out in the mornings between 07:00
and 09:00 in forest, and between 18:00 and 19:00 at forest edge. Two
counts were carried out each morning, the first being at a randomly
m
selected point along a path, at least 500 into forest. The second count
m
was carried out 300 (and no more than 15 minutes walk) from the
firstpoint in a directline walked on a easterly compass bearing.
m
Only birds within a fixed radius of 25 (estimate of error is 3 m,
m
12%) and 3 above the ground were recorded. Each point was sampled
for 40 minutes with observations being allocated to 5 minute time
intervals giving scores of between 0 and 8 over the sample period. All
other methods followed Bennun and Waiyaki (1992) All counts were
madeby the same two observers (Marc Baker and Njano Mbilinyi)
The results from Loima were compared with those from other
northern dry montane forests, in particular Kulal and Njiru (Borghesio
pers. comm.) and Moroto (Davenport et al. 1996). The main aim was to
look at the similarity of these sites in terms of the avifauna known to
occur, using Bray-Curtis cluster analysis. This uses group-average
clustering to give a hierarchy of clusters indicating similarity as a
percentage. The analysis concentrates on the forest dependant avifauna
(both forest specialist and forest generalist) as defined by Bennun et al
1996.
Results and discussion
A total of 87 species were recorded, representing 40 families and
including three species of conservation concern (Bennun & Njoroge
1996). A full list is shown in the appendix. Of these 87 species, 48 were
recorded in Eminit Forest and at forest edge (above 2050m), whilst the
m
remainder were recorded in the dry Acacia woodland between 800 (at
the foot of the Loima Hills) and 2050 m.
Mist netting
A total of 2616 net-metre-hours (nmh) were completed over a five-day
period, in which 13 birds were caught and processed (Table 1). The low
number of captures reflects the low effort but also the low capture rate
of 0.004 birds per nmh. This was probably due to the lack of a shrub
layer within the forest which would normally help conceal the nets.
Table 1. Results frommist-nettingin EminitForest.
Species Ecol.Type No.caught Rank
White-eyedSlatyFlycatcher F 3 1
Scaly-throated Honeyguide f. 2 2
Grey-backedCamaroptera f. 2 2
BrownWoodlandWarbler F 3
YellowWhite-eye f. 3
Brown-headedTchagra Fe 3
Cape-RobinChat f. 3
AmethystSunbird f. 3
VariableSunbird f. 3
24 Marc Baker
Almost all of the birds caught and ringed were forest species: two forest
generalists (F), six forestusers (f.) and one forest edge (fe) species.
Timed species counts
A total of 16 TSCs were carried out in forest interior and forest edge,
giving a species list and index of relative abundance for each habitat
type. The results for the timed species counts are shown in Tables 2 and
3 which indicate the commonest canopy and mid-stratum species in
both the forest interior and forestedge.
In the forest interior, ten TSCs were carried out during which 13
species were recorded (Table 2). African Goshawk Accipiter tachio, Olive
Pigeon Columha arquatrix, Narina Trogon Apaloderma Narina and Brown
Woodland Warbler Phylloscopus umbrovirens were recorded only in forest
interior.
Table 2. Results oftimed species countsinforestinterior, EminitForest.
Species Ecol.Type TSCIndex Rank
BrownWoodlandWarbler F 4.0 1
OliveThrush F 2.0 2
Grey-backedCamaroptera f. 1.9 3
DuskyFlycatcher F 1.4 4
White-eyedSlatyFlycatcher F 0.9 5
GreyCuckooShrike FF 0.8 6
AmythstSunbird f. 0.8 6
YellowWhite-eye f. 0.8 6
Olive Pigeon F 0.7 7
DuskyTurtle Dove f. 0.7 7
AfricanGoshawk F 0.6 8
Common Bulbul f. 0.5 9
NarinaTrogon F 0.2 10
At forest edge, six TSCs were carried out in which 15 species were
recorded (Table 3). Variable Sunbird Cinnyris venusta, Cape Robin-Chat
Cossypha cajfra, Baglafect Weaver Ploceus haglafect, Northern Puffback
Dryossvopus gambensis, Paradise Flycatcher Terpsiphone viridis and
Yellow-crowned Canary Serinus canicollis were all recorded only at
forest edge.
Table 3. Results oftimed speciescounts along forestedge,EminitForest.
Species Ecol.Type TSCIndex Rank
VariableSunbird f. 5.3 1
AmethystSunbird f. 4.5 2
YellowWhite-eye f. 3.6 3
Common Bulbul f. 3.6 3
Cape Robin Chat F 3.5 4
BaglafectWeaver f. 2.6 5
OliveThrush F 2.6 5
Northern Puffback F 1.3 6
Grey-backedCamaroptera f. 1.3 6
GreyCuckooShrike FF 1.1 7
Paradise Flycatcher F 1.1 7
YellowCrownedCanary f. 1.1 7
DuskyFlycatcher F 0.6 8
White-eyedSlatyFlycatcher F 0.6 8
DuskyTurtle Dove f. 0.3 9
Avifauna of Eminit Forest, Loima Hills 25
Species accounts
Great Sparrowhawk Accipiter melanoleiicus (dark morph) was recorded
four times carrying food in the same direction at dusk and thus
suspected to be breeding. As all observations of this species were of a
dark morph in the same location at approximately the same time it was
presumed that this was the same individual.
Peregrine Falcon Falco peregrinus was recorded daily at dusk hunting
over grassland. The presence of cliffs which this species requires for
breeding make it likely that this was a residentbird. Heavy streaking on
the breast indicated that this was a sub-adultbird.
White-crested Turaco Tauraco leucolophus was recorded in forest edge
and riverine forest as low as 1800 m. It was absent from the forest
interior and the dry woodlandbelow 1800 m.
African Hill Babbler Alcippe abyssinica was recorded throughout the
forested plateau. Cunningham-van Someren and Schifter (1981)
described a separate race for Loima (loima) based on collections madeby
Joseph Mwaki in 1962.
Olive Thrush Turdus olivaceus was observed throughout habitat types
above 2000 m, where it was recorded feeding in the ground layer, sub-
canopy and canopy. This is usually a bird of the ground and shrub layer,
so it is thought that the absence of a shrub layer combined with a lack of
resource competition from greenbuls and hornbills (see below) may
have allowed this species to occupy the canopy layer. Cunningham-van
Someren and Schifter (1981) make reference to the sharp division
between the extremely pale birds from Loima, Morongole, Karissia,
Nguruman Range and those from other areas.
Brown Woodland WarblerPhylloscopus umbrovirens was the commonest
bird in the forest interior (see TSC results. Table 2). A bird usually
associated with shrub layer and small trees, this species predominantly
occupied the sub-canopy and canopy, and was often recorded crawling
through theJuniperus-Podocarpus canopy at over 30 m.
Cinnamon Bracken Warbler Bradypterus cinnamomeus was recorded
twice in the undergrowth of forest clearings created by felled trees and
imdergrowth along drainage lines within the forestinterior.
Baglafect Weaver Ploceus baglafect emini, is distributed in woodland and
m m
marsh between 800 and 1200 from north-west Uganda east to the
Loima Hills. It was recorded in forest edge and clearings where it was
relatively abundant (see TSC results. Table 3); several juvenile birds
were also recorded.
Large numbers of swifts mainly African Black Swift Apus barbatus
(estimates of flock size over 250 individuals) but also significant
numbers of Alpine A. melba and Mottled Swift A. aequatorialis (estimates
of flock size over 50 individuals) were recorded daily, feeding above
grassland and along the edges of cliffs. Nyanza Swift A. niansae was
observed daily in mixed species flocks, but in considerably lower
26 Marc Baker
numbers than other members of this family (usually 3-4). Common
House Martin Delichon urbica were present in low numbers, often in
mixed flocks.
Comparison with other northern montaneforests
A comparison was made of species that have been recorded in the
similar northern dry montane forests of Kulal and Njiru (Borghesio
pers. comm.) and Moroto (Davenport et al. 1996). This comparison was
based on the forest dependant species (forest specialist FF, and forest
generalist F) for each site. Loima had 19 species, Moroto 28, Kulal 16
and Njiru 26. When looking at the similarity of these sites, all mountains
showed a high percentage in the similarity of their species composition,
the highest being shown by Moroto and Loima (68%) and the least by
Moroto and Kulal (55%, Table 4).
Table 4. Similarity matrix showing the percentage similarity between the
montaneforest sites.
SimilarityMatrix
Moroto Njiru Kulal
Loima 68.0851 66.6667 51.4286
Kulal 54.5455 66.6667
Njiru 62.963
Moroto * * *
The only species so far recorded at all of these sites were: Mountain
Buzzard Buteo oreophilus, Red-chested Cuckoo Cuculus solitarius, Narina
Trogon, African Hill Babbler Pseudoalcippe abyssinica, Olive Thrush,
Brown Woodland Warbler and Northern Puffback. The similarity
between Moroto and Loima is influenced by the presence of two species
in particular that have not been recorded at Kulal and Njiru, namely
Tambourine Dove Turtur tympanistria and African Wood Owl Ciccaha
woodfordii. Clearly, Moroto has the greatest diversity of forest dependant
species (n=28), with eight occurring only at that site. At Njiru (n=26)
there are four species unrecorded from Kulal and Loima, all species
typical of dry montane forests.
There were several groups of birds that were conspicuous by their
absence from Eminit. No members of the genus Apalis were recorded.
Yellow-breasted Apalis Apalis flavida, a bird of woodland and forest
edge, was expected to occur, and this absence maybe linked to isolation,
as it has not been recorded in the arid woodland of north-western
Kenya (Zimmerman et al. 1996). The absence of Grey Apalis Apalis
cinerea, an active bird found in the canopy of similar montane forest,
cannot be linked to habitat variables. It would almost certainly have
been recorded were it present. Chestnut-throated Apalis Apalis
porphyrolaema has been recorded in Moroto and in isolated montane
forests south of Loima. The absence of any greenbuls, Cabanis's
Greenbul Phyllastrephus cabanisi in particular, is odd. Resource
Avifauna of Eminit Forest, Loima Hills 27
availability does not appear limited for an insectivorous bird such as
this, which does occur on Moroto, Kulal and Njiru. This species is
commonly caught in mist-nets so should have been recorded if present.
Yellow-whiskered Greenbul Andropadus latirostris is another likely
species that was not recorded. This bird is predominately frugivorous
and very few sub-canopy fruiting shrubs or trees were noted. Northern
Brownbul Phyllastrephus strepitans, a bird of woodland and forest edge,
was also expected to occur since the habitat and resource availability
would seem to suit this species. Silvery-cheeked Hornbill Bycanistes
hrevis was not recorded despite the presence of fruiting figs and the
large trees required for nesting by this species. The absence of White-
starred Forest Robin Pogonocichla stellata is unusual because this species
is found in the lower stratum of these forest types and occurs on many
isolated forest islands in Kenya and Tanzania, supporting the fact that
this species has a good ability to disperse. Abyssinian Ground Thrush
Zoothera piaggiae occurs on Kulal, Njiru and Moroto but is absent at
Loima.
There are several reasons why these species may be missing
including: 1) they were missed by the survey team, although this is
unlikely for those species which are vocal or gregarious (e.g. some of the
apalises); 2) some aspect of the habitat was unsuitable. The stratification
of the vegetation seemed to have a large impact on avian diversity, and
the feeding ecology of many of the bird species. Many of the species
normally associated with undergrowth were notably absent, while
insectivorous and omnivorous species one would normally associate
with undergrowth were regularly observed in the sub-canopy and
canopy 3) they have been unable to colonise the site due to poor
dispersal ability and/or lack ofhistorical habitat connectedness.
White-browed Robin-Chat Cossypha heuglini was collected in the
Loima Hills in 1962 by Joseph Mwaki for A.D. Forbes-Watson, but was
not recorded during the current survey.
Threats and conservation recommendations
The threats to biodiversity at this site are varied. Firstly, the presence of
fire arms has almost certainly greatly reduced wildlife populations.
Although dikdik are fairly common, these were the only "large''
mammals that were observed in the acacia woodland. It is unlikely that
opportunistic hunting with firearms would affect the avifauna as the
cost of a single round would not be justified by the meat gained.
However, gunfire was heard several times during this two week survey
suggesting that ammunition was nothard to obtain.
The large amounts of fuel wood still available around the Loima
Hills and within Eminit Forest would indicate that felling trees for
firewood by local people is not a cause of concern. Within Eminit Forest
there were no signs of felling for fuelwood or timber, though several
trees had beenburnt for wild honey. In a couple of instances, Podocarpus
28 Marc Baker
falcatus were felled for seemingly no apparent reason other than to allow
light through to the forest floor and create grazing for future use.
The major conservation concern encountered was charcoal
production. This activity is mainly restricted to the Acacia tortillis
riverine woodland running from the Loima Hills east to Lodwar. The
demand for charcoal is generated in Lodwar where the increasing
populationhas led to an increased demand for fuel.
The indigenous land-use system previously outlined, is born of an
understanding of the need for dry season grazing (for herbaceous
production levels see Barrow 1988). The land-use systems that are in
place are designed around a model of sustainability to ensure that this
resource is protected in perpetuity for times of environmental stress. In
terms of the conservation of biodiversity, the current land-use system
would seem to be beneficial with the current land-users also being its
guardians. However, as stated by Barrow (1988), the presence of a legal
framework that acknowledges the current land-use system as well as
allowing a measure of protected status is essential. Whereas definitions
of protected areas such as Game Reserve, National Reserve and
Biosphere Reserve are based on the exclusion of people and
preservation of the natural resource to varying degrees, the best option
for Loima would be a Forest Conservation Reserve with its own rules
and regulations (Barrow 1988).
Conclusions
This preliminary survey shows Eminit Forest to have a relatively poor
avifaunal diversity with only 19 forest dependent species of which four
are forest specialists. Due to its northerly location it does represent an
isolated outlier of this montane forest type, and as with other isolated
mountains, Eminit represents an important refuge for the movement of
birds as well as other wildlife and people. Although only four forest
specialist species have so far been recorded at this site, Eminit Forest's
effect on local rainfall patterns, water drainage and thus vegetation
biomass over a large area is clear (Barrow 1988, Amuyunzu & Oba
1991). As such, Eminit Forest is of significance for many species of birds
and wildlife that, although they are not truly forest dependant species,
are very much dependant on the presence of the forest.
Acknowledgments
Many people aided this field project. Thanks to all the staff at the UNDP/GEF
Crossborder Biodiversity Project in Nairobi and Lodwar, in particular Mr.
George Ondenge, Mrs. Rose Antibo, Mr. Moses Lekong, Mr. Richard Musee
and Mr. Japheth Katembo. I amextremely grateful to Dr. Leon Bennun and Mr.
Luca Borghesio for their prompt email responses and to Dr. Alan Rodgers for
his technical advice. Special thanks go to my field team, Mr. Njano Mbilinyi,
Avifauna ofEminit Forest, Loima Hills 29
Mr. David Gitau and Miss. Lauren Persha for their valuable contributions and
Mr.Jo Andersonforproofing the final drafts.
References
Amuyunzu, C.L. and Oba, G.1991. Vegetation Resources of Central Turkana
District, Kenya. UNESCO.
—
Barrow, G.C. 1988, Loima Forest, Turkana Its present management andfuture con-
servation issues. TurkanaRural DevelopmentProgram (NORAD).
Bennun, L.A. and Waiyaki, E.M. 1992. Mau Forest Complex Ornithological Survey
Report. NationalMuseums ofKenya.
Bennun, L.A., Dranzoa, C. & Pomeroy, D. 1996. The forest birds of Kenya and
Uganda.Journal oftheEastAfrican NaturalHistory 85: 23-48.
Bennun, L.A. and Njoroge, P. 1996. Birds to watch in East Africa: A preliminary
Red Data list. Nairobi: The NationalMuseums ofKenya.
Britton, P.L. 1980. (ed) Birds of East Africa. Nairobi: The East Africa Natural
HistorySociety.
Cunningham-van Someren, G.R. & Schifter, H. 1981. New races of montane
birds from Kenya and southern Sudan.Bw/Zefm of the British Ornithologists'
Club
EANHS
1996. Check-list of the birds ofKenya. Nairobi: Ornithological sub-com-
mittee. EastAfricaNaturalHistorySociety.
Davenport, T. and Howard, P. 1996. Moroto Forest Reserve, Biodiversity Report.
Kampala: UgandaForestDepartment.
Lewis, A. & Pomeroy D. 1989. A bird Atlas ofKenya. Rotterdam: A. A. Balkema
Publishers.
Oba, G. 2001. Reporton theevaluation ofbiodiversity in crossborders ofeastAfricafor
F.A.O. The Turkanasites ofKenya. Noragric.
Zimmerman, D. A., Turner, D. A. & Pearson, D. J. 1996. Birds ofKenyaand north-
ern Tanzania. SouthAfrica: RusselFriedmanBooks.
30 Marc Baker
Appendix
Bird species recordedfrom the foot ofLoimaHills at800mto theforested
plateau at2100m. Taxonomic order follows EANHS (1996) withtheirr\umber
indicated. TheKenyanbird atlas squarenumberis given for each species
following Lewis & Pomeroy (1989). Those species whichare ofparticular
conservationsignificance are indicated as: RNT=RegionallyNearThreatened,
RVu=RegionallyVulnerable and RR=RegionallyRestricted (Bennunand
Njoroge 1996). Ecological type for forestbirdsfollows Bennunetal. (1996);
FF=forestspecialist, F=forest generalist and f.=forestvisitor. The remaining
non-forestbirds are categorised as follows: W=Widespread,Wd=Woodland,
G=Grassland and Fe=Forestedge. Breeding records are indicated as:
SusBr^Suspectedbreeding andBr=Confirmedbreeding.
No Family/English name Scientificname Ecol.type Atlassq.
AccipitridaG
1ui bwailow-1aiieaMie OfielictiniBnocouni Wd 130
\Vd DiacKi\iie Milvusmigrdns G 130 12D
1 1/ narnerriaWK roiyuoroioeslypnus f. 130 12D
125 AfricanGoshawk Accipitertachio F 130
127 Shrika Accipiterbadius f. 130
104 urealoparrowriaWK MccipiieriTieidnuieucus F 130 12D
139 Mountain Buzzard Buteooreophilus FF 130 12D
W
142 AugurBuzzard Buteoaugur 130
W
158 Martial Eagle Polemaetusbellicosus 130
159 PygmyFalcon Polihieraxsemitorquatus Wd 130
162 PeregrineFalcon Faicoperegrinus Fe 130 12D
iDD Mincan noDDy ralCOcuvieri F 130 12D
1/4 roxi\esTrei FaIcoalop6x Wd 130
Phasianidae
lyu uresiearrancoiin FrancolinusSBphaena Wd 130
Glareolidae
257 SomaliCourser Cursoriussomalsnsis Wd 130
ririliimhirlap
357 TambourineDove Turturtympanistria F 130 12D
359 Emerald-spottedWood Dove Turturchalcospilos f. 130
365 OlivePigeon Columbaarquatrix FF 130
366 Speckled Pigeon Columbaguinea Wd 130
371 MourningDove Streptopeliadecipiens Wd 130
376 DuskyTurtleDove Streptopelialugens f. 130 12D
Musophagidae
399 White-crestedTuraco Tauracoleucolophus f. 130 12D
401 White-belliedGo-away-bird Corythaixoidesleucogaster Wd 130
Cuculidae
409 Red-chestedCuckoo Cuculussolitarius F 130 12D
417 EmeraldCuckoo Chrysococcyxcupreus F 130 12D
419 Klaas'sCuckoo Chrysococcyxklaas F 130 12D
422 White-browedCoucal Centropussuperciliosus Fe 130
Strigidae
444 WoodOwl Ciccaba woodfordii F 130
Caprimulgidae
449 MontaneNightjar Caprimulquspoliocephalus F 130 12D
460 Slender-tailedNightjar Caprimulqusclarus Wd 130
